title: Involvement of AP-1 and NF-κB in the up-regulation of P-gp in vinblastine resistant Caco-2 cells.
abstract: Caco-2 is a widely used cell model in drug absorption and P-glycoprotein (P-gp, MDR1) substrate identification. Long-term vinblastine treatment of Caco-2 cells could increase the expression of P-gp; thus, the vinblastine resistant Caco-2 (Caco-2 vbl) cells can be used as a rapid and sensitive alternative model in identifying P-gp substrates. The mechanism of P-gp induction in this model is not clear; this study was therefore intended to clarify the possible factors involved in P-gp up-regulation in Caco-2 vbl cells. Since vinblastine is the inducer of both activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB), we investigated the role of AP-1 and NF-κB in the regulation of MDR1 gene expression. Our results indicated that the AP-1 and NF-κB luciferase activity was higher in Caco-2 vbl cells than that in Caco-2 cells according to reporter gene assay. The mRNA expression of AP-1 subunit c-Jun and NF-κB was increased in Caco-2 vbl cells. The c-Jun inhibitor SP600125 and NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) suppressed the expression of MDR1 mRNA in Caco-2 vbl cells. In conclusion, this study provides the evidence that AP-1 and NF-κB are involved in the P-gp induction in Caco-2 vbl cells.
authors.affiliation: Laboratory of Pharmaceutical Analysis and Drug Metabolism, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University.
authors.forename: Qiuxia
authors.initials: Q
authors.lastname: Chen
authors.forename: Yicong
authors.initials: Y
authors.lastname: Bian
authors.forename: Su
authors.initials: S
authors.lastname: Zeng
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics / Q000378:metabolism; D000873:Anthracenes / Q000494:pharmacology; D001665:Binding Sites; D018938:Caco-2 Cells; D004351:Drug Resistance; D017930:Genes, Reporter; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011759:Pyrrolidines / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013859:Thiocarbamates / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D015854:Up-Regulation; D014747:Vinblastine / Q000494:pharmacology*
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D000873:Anthracenes; D016328:NF-kappa B; D011759:Pyrrolidines; D012333:RNA, Messenger; D013859:Thiocarbamates; D018808:Transcription Factor AP-1; C432165:pyrazolanthrone; C020972:pyrrolidine dithiocarbamic acid; D014747:Vinblastine; D008156:Luciferases